WASHINGTON — Health care guru Donald Berwick is staking much of his campaign for Massachusetts governor on the lead role he played, as head of a key Washington agency, in helping kick off President Obama’s new health coverage law.

But now that the much-anticipated debut of the government’s online insurance marketplace has turned into a frustrating mess, Berwick is at a loss to explain the failures. He said he was not involved in crucial strategy and contracting decisions made during his tenure that dictated how his agency, the Centers for Medicare and Medicaid Services, would build the computer network.

The web portal is critically important to the political and practical success of the Affordable Care Act, because it is supposed to allow millions of newly empowered consumers to smoothly purchase plans. Yet Berwick said in an interview this week that he did not see launching the marketplace computer network as a major part of his role as chief of the agency.

“Those were staff level functions,” Berwick said. “My leadership investment was in the vision of CMS as a major force of improvement of care for the nation.”

Berwick said he does not remember any discussion, for instance, of a decision that is the focus of intense second-guessing in Congress: having agency administrators oversee development of the online marketplace, rather than hiring an outside management company with stronger technical expertise to coordinate the complex project.

“It certainly wasn’t me who made the decision. It must have been lower down in the organization. I don’t recall,” Berwick said. Still, Berwick defended the move.

“The decision to keep it a CMS function makes sense,” he said, citing data security concerns as a reason not to outsource oversight to a company. “It’s a highly competent agency accustomed to managing data and data systems.”

Berwick served as administrator of the Centers for Medicare and Medicaid Services at an important juncture. Obama installed him while Congress was in recess in July 2010, four months after the Affordable Care Act was passed, bypassing what would have been a difficult Senate confirmation fight. Berwick departed in December 2011, as his recess appointment was set to expire.

Analysts have said the crippling problems that have emerged in the marketplace portal — frozen programs, inaccurate data, inaccessible web sites — are rooted in the construction of the network, which took place in the two years after Berwick left. But it was during the 17 months of Berwick’s leadership that the agency issued regulations and contracts that set the trajectory for the work to proceed, with what critics in hindsight say was insufficient oversight and testing.

“The most important time for establishing the [insurance marketplace] was when Don was the head of CMS. That would have been the time when the most important foundational work was done,” said Jay Angoff, a former official at the Department of Health and Human Services who was involved in planning for the law in 2010.

The Centers for Medicare and Medicaid Services spent nearly $394 million through March 2013 on contracts related to building the federal insurance marketplace, according to a June Government Accountability Office report. Current estimates now put the cost at around half a billion dollars.

Berwick blamed many of the latest technical problems on a lack of money set aside for the massive undertaking, a result of the toxic political climate and Republicans’ singular focus on dismantling the law. The government’s role grew substantially when state after state refused to set up their own insurance marketplaces, leaving it to the federal government to run them in 36 states.

“This was done under quite tight resource constraints,” Berwick said. “We did as well as we could under the resources that we had.” With more money, Berwick said, the agency could have conducted more tests.

“I can’t say that nothing should have been done differently, with the benefit of hindsight,” Berwick said.

Widely admired in health care circles as a visionary, Berwick is a former Harvard Medical School professor and founder of Cambridge-based Institute for Healthcare Improvement, where he is now a fellow. He arrived at CMS as a government outsider whose expertise was in improving health care delivery, preventing medical errors, and containing costs. Navigating the intricacies of the Washington bureaucracy and administering contracts were never considered his strong points.

Berwick said he and his staff focused primarily on parts of the law that were to take effect before the marketplaces opened, such as allowing young adults to stay on their parents’ insurance until age 26. Berwick himself was much more engaged in increasing the availability of preventative care and issuing regulations for “accountable care organizations,’’ which are intended to align physician incentives for more efficient treatment.

Still, questions about the nuts-and-bolts of computer contracting and oversight are causing a political uproar now, leading Obama to vent his frustration this week.

The day before Berwick’s tenure ended in 2011, CMS awarded the largest contract, worth up to $93.7 million, to CGI Federal Inc., a Montreal-based firm. The company is now at the center of congressional investigations into what went wrong and who was at fault. Its representatives will be testifying at a House Energy and Commerce Committee hearing on Thursday.

Hunting for what went wrong in development of the marketplace, the House Committee on Oversight and Government partly has zeroed in on the lack of a “system integrator,” or contract manager, to pull together the complex details and ensure the data systems all fit together smoothly.

CGI officials voiced concerns in January during a briefing with committee staff that there was a “lack of coordination and abundance of confusion between stakeholders involved in setting up the website,” according to a letter committee members sent to administration officials this week.

The CGI officials also expressed doubts that the website, healthcare.gov, would be operational by the Oct. 1 deadline, telling committee staff they needed “more direction on budgetary and project governance.”

Berwick said he has not been asked by any committee to testify. Health and Humans Services Secretary Kathleen Sebelius, who is weathering intense criticism in the capital for the system’s failures, will appear before the Energy and Commerce Committee next week.

Berwick, a Democrat, says government has a “moral” duty to protect children, seniors, the sick, and the otherwise disenfranchised. He calls Obama’s health reform a “majestic law.” In soaring rhetoric at a conference in December 2011 a few days after he resigned at CMS, Berwick highlighted his “chance to help pilot toward harbor the most important health care policy of our time.”

But for a law, just an “architect’s sketch,” to impact real people, it must be “transformed into the specifications that regulations and guidance documents,’’ Berwick said then.

“On my expedition,” he said, “that, mostly, was what I was doing.”

In response to questions, Berwick said he was unsure why his agency did not rely more heavily on the successful Massachusetts Connector, the state’s groundbreaking version of a digital healthcare marketplace, as a model, instead of engineering new systems.

Berwick said the federal marketplace is vastly larger and more complex than the Massachusetts version because it must interact with multiple databases, including the Internal Revenue Service.

The federal marketplace is also supposed to give an instantaneous calculation of the amount of subsidies for which consumers qualify; the Massachusetts web portal did not.

But complexity alone does not explain why faulty code, weak testing, and missed deadlines are now plaguing the federal system, say experts, who contend the government’s arcane IT procurement regulations and the slow grind of bureaucracy make it ripe for embarrassing mishaps. The process favors vendors such as CGI that have relationships with federal agencies and shuts out smaller firms that can more easily innovate and may be better for the job, they say.

“It seems to me like the wrong people were in charge,” said Clay Johnson, founder of Blue State Digital, the technology strategy behind Obama’s 2008 campaign,
“It’s very clear that whoever signed off on the launch of this website didn’t actually do any of the tests required for the website to be released.”

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